Since the network just went online and it doesn’t have an established user base, it will be several months before we start seeing reliable figures from testing companies like RootMetrics or OpenSignal, but we can get idea of how T-Mobile’s network will perform based on what we know about the spectrum and the technology its using. As I’ve detailed before, no two LTE networks are created equal, and T-Mobile has some advantages that will help its 4G service outpace its competitors.

We can expect to see some correlation between those speeds and T-Mobile’s after it loads its new 4G network up with subscribers. But T-Mobile isn’t stopping there.

Neville Ray, CTO, T-Mobile (c) 2012 Pinar Ozger pinar@pinarozger.com

As T-Mobile CTO Neville Ray refarms more 3G spectrum for LTE, he will be able to boost many of its 10 MHz systems to a full 20 MHz, but the real prize comes after it closes its acquisition of MetroPCS (which at this point seems almost a given). Surgically adding Metro’s AWS spectrum to the current network will give it 40 MHz of LTE in some key markets. That’s twice the capacity of the systems currently run by Verizon and AT&T.

Sometimes it pays to wait

As for technology, let’s just say there are some advantages from being late to market.

Technically even T-Mobile’s most modest 10 MHz network could today support a theoretical downlink of 37.5 Mbps (though real-world network speeds would be much less) when connecting to the latest and greatest devices. Once it gets to the 40 MHz networks, however, T-Mobile’s 4G service would be truly awe-inspiring, boasting a theoretical ceiling of 150 Mbps.

Of course, 150 Mbps may seem a bit ridiculous for your typical smartphone user, but the justification for those speeds isn’t to create individual super connections, but to produce more capacity that can be shared by more users. The more data T-Mobile can deliver to a large subset of user, the cheaper it can make data pricing. And making data cheaper is one of the main ways T-Mobile is setting itself apart from the competition.